4 * Author: Martyn Welch <martyn.welch@ge.com>
5 * Copyright 2009 GE Intelligent Platforms Embedded Systems, Inc.
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/errno.h>
18 #include <linux/device.h>
19 #include <linux/platform_device.h>
20 #include <linux/ctype.h>
21 #include <linux/gpio.h>
22 #include <linux/slab.h>
23 #include <linux/vme.h>
27 static const char driver_name[] = "pio2_gpio";
29 static struct pio2_card *gpio_to_pio2_card(struct gpio_chip *chip)
31 return container_of(chip, struct pio2_card, gc);
34 static int pio2_gpio_get(struct gpio_chip *chip, unsigned int offset)
38 struct pio2_card *card = gpio_to_pio2_card(chip);
40 if ((card->bank[PIO2_CHANNEL_BANK[offset]].config == OUTPUT) |
41 (card->bank[PIO2_CHANNEL_BANK[offset]].config == NOFIT)) {
43 dev_err(&card->vdev->dev, "Channel not available as input\n");
47 retval = vme_master_read(card->window, ®, 1,
48 PIO2_REGS_DATA[PIO2_CHANNEL_BANK[offset]]);
50 dev_err(&card->vdev->dev, "Unable to read from GPIO\n");
55 * Remember, input on channels configured as both input and output
58 if (reg & PIO2_CHANNEL_BIT[offset]) {
59 if (card->bank[PIO2_CHANNEL_BANK[offset]].config != BOTH)
64 if (card->bank[PIO2_CHANNEL_BANK[offset]].config != BOTH)
71 static void pio2_gpio_set(struct gpio_chip *chip, unsigned int offset,
76 struct pio2_card *card = gpio_to_pio2_card(chip);
78 if ((card->bank[PIO2_CHANNEL_BANK[offset]].config == INPUT) |
79 (card->bank[PIO2_CHANNEL_BANK[offset]].config == NOFIT)) {
81 dev_err(&card->vdev->dev, "Channel not available as output\n");
86 reg = card->bank[PIO2_CHANNEL_BANK[offset]].value |
87 PIO2_CHANNEL_BIT[offset];
89 reg = card->bank[PIO2_CHANNEL_BANK[offset]].value &
90 ~PIO2_CHANNEL_BIT[offset];
92 retval = vme_master_write(card->window, ®, 1,
93 PIO2_REGS_DATA[PIO2_CHANNEL_BANK[offset]]);
95 dev_err(&card->vdev->dev, "Unable to write to GPIO\n");
99 card->bank[PIO2_CHANNEL_BANK[offset]].value = reg;
102 /* Directionality configured at board build - send appropriate response */
103 static int pio2_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
106 struct pio2_card *card = gpio_to_pio2_card(chip);
108 if ((card->bank[PIO2_CHANNEL_BANK[offset]].config == OUTPUT) |
109 (card->bank[PIO2_CHANNEL_BANK[offset]].config == NOFIT)) {
110 dev_err(&card->vdev->dev,
111 "Channel directionality not configurable at runtine\n");
121 /* Directionality configured at board build - send appropriate response */
122 static int pio2_gpio_dir_out(struct gpio_chip *chip, unsigned offset, int value)
125 struct pio2_card *card = gpio_to_pio2_card(chip);
127 if ((card->bank[PIO2_CHANNEL_BANK[offset]].config == INPUT) |
128 (card->bank[PIO2_CHANNEL_BANK[offset]].config == NOFIT)) {
129 dev_err(&card->vdev->dev,
130 "Channel directionality not configurable at runtine\n");
141 * We return whether this has been successful - this is used in the probe to
142 * ensure we have a valid card.
144 int pio2_gpio_reset(struct pio2_card *card)
151 /* Zero output registers */
152 for (i = 0; i < 4; i++) {
153 retval = vme_master_write(card->window, &data, 1,
157 card->bank[i].value = 0;
160 /* Set input interrupt masks */
161 for (i = 0; i < 4; i++) {
162 retval = vme_master_write(card->window, &data, 1,
163 PIO2_REGS_INT_MASK[i * 2]);
167 retval = vme_master_write(card->window, &data, 1,
168 PIO2_REGS_INT_MASK[(i * 2) + 1]);
172 for (j = 0; j < 8; j++)
173 card->bank[i].irq[j] = NONE;
176 /* Ensure all I/O interrupts are cleared */
177 for (i = 0; i < 4; i++) {
179 retval = vme_master_read(card->window, &data, 1,
180 PIO2_REGS_INT_STAT[i]);
189 int __devinit pio2_gpio_init(struct pio2_card *card)
194 label = kmalloc(PIO2_NUM_CHANNELS, GFP_KERNEL);
196 dev_err(&card->vdev->dev, "Unable to allocate GPIO label\n");
200 sprintf(label, "%s@%s", driver_name, dev_name(&card->vdev->dev));
201 card->gc.label = label;
203 card->gc.ngpio = PIO2_NUM_CHANNELS;
204 /* Dynamic allocation of base */
206 /* Setup pointers to chip functions */
207 card->gc.direction_input = pio2_gpio_dir_in;
208 card->gc.direction_output = pio2_gpio_dir_out;
209 card->gc.get = pio2_gpio_get;
210 card->gc.set = pio2_gpio_set;
212 /* This function adds a memory mapped GPIO chip */
213 retval = gpiochip_add(&(card->gc));
215 dev_err(&card->vdev->dev, "Unable to register GPIO\n");
216 kfree(card->gc.label);
222 void pio2_gpio_exit(struct pio2_card *card)
224 const char *label = card->gc.label;
226 if (gpiochip_remove(&(card->gc)))
227 dev_err(&card->vdev->dev, "Failed to remove GPIO");